DST is focused on shining a light on advancements in technologies that can increase productivity, decrease overall cost and simplify the environment, as we believe that data trends in the marketplace warrant the need for a re-think in how we manage and store data.

The first such advancement is Storage Virtualization. Storage Virtualization works in much the same way as server virtualization.  There is an abstraction between the physical hardware (the array) and the processing of the data.  Whether a structured data environment (SAN) or an unstructured data environment (NAS) the data management and ownership is abstracted from the hardware that the data resides on, creating a flexible central point of management for the entire heterogeneous resource pool.  The advantages of virtualization:

• Create unparallel data mobility, fluidly assigning data to storage resources.
• Easily control and manage multiple physical resources from a single pane of glass.
• Flexibly set policies across entire ecosystem or volume by volume.
• Ability to commoditized infrastructure as the intelligence is divorced from hardware.
• Platform agnostic replication and virtualization.

Replication, Disaster Recovery and Backup is another area of technology convergence. All of these functions can be done now in a single piece of software from a single pane of glass more efficiently, with better recovery points and recovery times. Backup vendors are integrating with storage snapshot technology, storage vendors are able to create more snapshots and business continuity/disaster recovery product vendors are integrating file level catalogs – all evidence of several markets collapsing as technology advances.

Another popular topic of conversation is SSD. SSD Augmentation and Cloud-based Storage i.e. “Amazon”-esque storage are two areas of hardware evolution that will dominate the storage industry in the years ahead.  The price point between SAS/FC drives and SSD drives is narrowing.  The SSD technology is improving its longevity of use and addressing other issues that kept it from broad acceptance.  Performance benefits from SSD are game changing in some environments – VDI in particular offers users a much different experience when it is on SSD.

Object based storage which is the productizing of the technologies that Amazon and Rack Space have been using for years offers organizations to rethink how they do business.  Especially in the entertainment industry – the question becomes “what would I do if storage costs went on sale at 70% off or more” – what would you keep on line available for customers or for internal use if cost were not a factor.

DST as an organization works with customers to consultatively look through the emerging technologies and create options that have value to your specific needs.

EMC certainly has the broadest addressable market, with the VNX for the mid-tier SAN/NAS customer and Isilon for the scale-out Petabyte imaging applications, however, the VNX is merely a Clariion with 25 year old technology sitting behind a Celerra NAS gateway. They were able to craft a unified message merely by uniting the management of each in a single GUI. Now, I am not saying that this is all together bad, but this has proven to have scalability and performance issues in the past and although components are faster, the underlying bottlenecks have not changed. This is why Isilon will play a more strategic role for EMC in the future. Isilon is a scale-out NAS platform. Adding nodes increases performance linearly and reduces overall overhead of the system. Due to the architecture, Isilon is more geared for large file NAS deployments (in particular, the way in which Isilon handles Level 1 and Level 2 caching within the system) and is not really a unified platform.

Hitachi BlueArc NAS with an AMS 2000 series behind it shares much of the same inefficiencies as the VNX and it not a true unified platform. It has however found its niche in its ability to address Billions of small files efficiently.

Until recently, I had not had much deep technical experience with new age file systems such as ZFS (Zettabyte File System) and CASL (Cache Accelerated File System). Like NetApps WAFL, ZFS, found as the basis for Oracle’s Unified Platform, Nexsan’s E5000 and IceWEB, is a WIFS (Write In Free Space) file systems. This makes them extremely efficient as blocks are not over-written, but written to free space, updating the file system index with the new location. CASL which runs at the heart of Nimble Storage is a file system always writes in stripes across the whole disk group. One could argue that this makes compression more efficient and increases performance for random workloads.

The contention for the past several years has been centered around the limitations of the file system to effectively manage the transactional nature of the index. The addition of SSD into ZFS and CASL file system architectures reduces this bottleneck even during high IO transactional workloads. Each of these “next generation” unified platforms can accommodate Fibre Channel, iSCSI, NFS, CIFS, WebDAV, HTTP as well as a host of other protocols. Furthermore, the flexibility of leveraging commodity oriented hardware makes these architectures cost effective.

These deserve the label virtualization tools because they are (or contain as part of them) create an abstraction layer between the host environment and the storage. I separate these products into two distinct groups; In-line Appliances or Storage Platforms.

In-line Appliances

The EMC VPLEX, Falconstor NSS and IBM SVC are all appliances that sit in the fabric between the hosts and storage. The all virtualize external storage and each has a set of storage vendors that are certified behind them.

The Falconstor NSS product has been out the longest of the three and is feature rich encorporating synchronous & asynchronous replication, snapshotting and thin (dynamic) provisioning. Like an active/active asynchronous SAN controller, a volume is owned by a particular NSS appliance. If a host image, such as a VM, lives in two places, only one can write at any one time. NSS is implemented in a clustered pair and there is a quorum to shift over ownership from one NSS appliance to another in the cluster. Asynchronous replication to a disaster recovery site is limited to Ethernet only.

The EMC VPLEX addressed a different concern – the ability to write from to the same volume from two different physical VPLEX engines and the VPLEX will manage through a separate 10G network and quorum the synchronization of the data that sits on EMC or non-EMC disk behind it. They have a fairly robust list of supported storage platforms on the matrix including the ability to virtualize other virtualization devices such as Hitachi’s VSP platform. This allows customers to achieve the ultimate in availability, data protection and mobility within and between datacenters. The EMC VPLEX is, however feature deficient today and EMC promises that this will change in the near future. All snapshotting and advanced provisioning are done at the platform being virtualized taking away some of the benefits that should be inherent in virtualization.

Although I have not encountered IBM’s SVC often and have not worked extensively with the product, it offers the ability to virtualize in the same manner as Falconstor and appears to have a reasonably complete set of provisioning and optimization features.

In-Line Storage Controller Virtualization

The Hitachi VSP is a unique breed of product expanding on the earlier USP-V technology. The VSP or Virtual Storage Platform is a storage subsystem and a virtualization engine in one. It provides all of the benefits of a Tier 0/1 storage platform with the ability to house internal disk with the ability to virtualize external storage. This is a double-edged sword as it provides the ability to provision, store data, tier within or externally and replicate within a single subsystem, however, the active/active unit is physically on chassis. Access, like with the Falconstor NSS and IBM SVC, is based on ownership. Only one VSP can have a host to LUN relationship at one time. VSPs can replicate synchronously or asynchronously over fabric.

Features and architecture greatly separate the storage virtualization platforms. When searching for a virtualization technology, first outline the goals your organizations requirements and put them in a priority order. Maybe I absolutely need complete mobility of applications and operating systems across synchronous distances. Maybe that is not as important as extending consistent advanced provisioning and snapshot functionality to several platforms that do not have the functionality today.

We are at an exciting time, especially in storage. The slow but steady adoption by the storage industry of external SAN storage virtualization has taken root, as evidenced by EMCs push with VPLEX, adds new possibilities and also complexities into the environment. Hitachi, IBM and Falconstor all offer a virtualization layer product, yet each is very different in capabilities and design. Virtualization is increasing being adopt in the NAS world as well to simplify migration and put a policy engine in front of the data. We also see the lines blurred – convergence between storage tool sets to augment backup, disaster recovery and business continuity and traditional backup products being more integrated at the storage layer. Customers are rethinking the entire backup paradigm that has existed for years.

This is fast becoming the decade of scale-out, scale up, scale over………… and the introduction of old technology in a new way is sweeping the scale-___ world. With the productizing of object-based storage, the Petabytes are becoming what used to be Megabytes. Scaling up to Exabytes is the new rage. With this technology comes a new method of access, removing the bloated file system and having applications track objects through an API or WebDAV access.

This blog hopes to shed some light into the world of storage and how customers can move tactically while making good strategic decisions for their enterprise.